Octopuses are characterized by their eight arms, usually bearing suction cups. Octopuses live in many places in the ocean, especially in coral reefs. There are many different types of octopuses, but they all have eight arms.
They eat mostly fish and small crabs. Some species of octopuses also eat other octopuses. The octopus is also called the devil fish. It has a special ink pouch that it uses to darken the water when it feels like it is in danger.

Many biologists think they are the most intelligent of the invertebrate animals. Most octopuses have only soft body with no skeleton. Because of this, it is very easy for an octopus to squeeze through very narrow openings between rocks. An octopus has three hearts. The octopus is capable of squeezing through a hole as big as his eye, this gives an idea about how flexible and slippery this animal can be.
Octopuses have a short life span, and some species live for as little as six months.